1. Field of the Invention
The present invention relates to a roller assembly for a machine that rotates a tire disposed on a vehicle and a method of making a roller assembly.
2. Background Art
Rollers are used on vehicle testing and steering alignment equipment such as dynamometers, vehicle roll testers, and toe-set alignment machines. A vehicle is positioned on such equipment so that its tires contact one or more rollers. Friction, heat, and pressure transfer contaminants from the tire to the roller when a tire rotates. These contaminants can include oil, steering fluid, dirt, tire dust, and other particulates. Contaminants accumulate on the outer surface of the roller and can interfere with equipment accuracy and performance. For example, in the case of a toe-set alignment machine accumulated contaminants on the surface of a roller can cause a tire to tilt. Tilting of the tire can result in inaccurate measurements and improper adjustments when attempting to correct misalignment conditions and associated warranty claims.
Manual cleaning operations are employed to remove contaminants from rollers as a regular maintenance item. Operators scrape the surface of the roller with paint scrappers and also may use chemical solvents to remove contaminants. Scraping is labor intensive and the use of chemical solvents is generally sought to be avoided in industrial facilities if possible.
Contaminants dislodged from the surface of the roller can infiltrate other components such as roller bearings, motors, and gear boxes. These loose contaminants can degrade equipment performance and increase wear, breakdowns, and associated maintenance expenditures. In addition, loose contaminants can accumulate underneath and between rollers, which impairs rotation of the roller and allows contaminants to redeposit on the surface of the roller.
The present invention is directed to providing a solution to one or more of these problems and others as summarized below.